I just picked up a Knight Elite Disc rifle,and was told by the counter person to use the 405 Grain Power Belt' s.Isn' t this a little heavy,considering i might run into shot' s out to 100 yds,or a bit further.What Grain Bullets ,show Good Accuracy out of the Knight Rifles? Ide really like to lessen my trajectory a bit,with something lighter,BUT accurate. Thank' s!